K&N Air Filter--worth the money?

[yiterp]

Thinking about picking up a K&N air filter for my Aspencade--is their a increase in performance?--are they worth the extra money? **==

[Keener]

Hey, Wyatt, long time no chat. How you been doin'?

I had a K&N for awhile but went back to the oem filter. The K&N was noisy and made no noticeable improvement. It cost me about $80 with the two oils.

[SIR tricky]

I have one on my second bike but only because it came with the bike. I wouldnt pay out for it.

I did buy the replenishing kit, that would be about the same price as a regular filter up here and it will last a while.

My bike does get excellent mileage but I wouldnt exactly point at the air filter for that.

[admin]

In theory the K&N filters are a great idea, but, in practice they don't seem to do as well unless you are constantly cleaning and oiling them. The oil coating seems to hold the dust tightly to the filter where it accumulates and then restricts airflow. For drag racing they are great because they offer low restriction and at the drags you don't mind cleaning the filter often for optimum performance but on a street bike the paper filter does a great job because when you shut the bike down much of the dust and dirt fall by gravity to the bottom of the air filter housing. I have 2 K&N filters on my workbench and I have a fresh paper air filter on my bike if that tells you anything.

[unionjack]

K&N filters are good at draining the wallet and dirtying up the intake. They will also make the engine much louder for the rider sitting in the cockpit of the bike.

I never saw any improvement in the bike, and the dirt in the intake was alarming so I went back to a paper filter and immediately noticed how much quieter the bike was for my ears.

my opinion is to save your money and stay with the paper filter, they will keep the carbs/engine clean and quiet.

[Granpah]

Wow!

I just bought a HiFlo filter ... but I cannot see any difference between the HiFlo and the K & N that sells for nearly four times as much.

[attachment=0]

THE SKEPTICAL 'WINGER

Trying to decide whether or not K & N has proven their claims somewhere, somehow, I went to the den of the beast: the K & N Homepage that claims:

Their opening statement is: "We believe the primary function of an air filter is to deliver both high airflow and superior dirt protection. We design our air filters to provide minimum restriction allowing high airflow into an engine." More about this wording, below.



Disposable Paper Air Filter

Pleated wood pulp bonded together.
As dirt builds, passages are plugged and filter must be replaced in approximately 10,000 miles.
Irregular passages filter out dirt on a go/no go basis.
As fibers swell from moisture or oil blow-by vacuum pressure increases and airflow decreases.
Turbulent filtered air.
and that


Typical Foam Air Filter

Lack of surface area hinders air flow and dirt holding capacity. Open cell foam usually saturated with oil.
Dirt builds on outside and blocks the openings.
Higher vacuum pressures distort the cells drawing dirt deeper into the filter.
Airflow is reduced as cells become blocked.
Turbulent filtered air.

HOWEVER, their own most "daring" claim is: "To ensure our air filters provide a high level of dirt protection, we regularly test our air filter designs using the testing procedure described above. Those tests demonstrate K&N air filters generally achieve overall filtration efficiency in the range of 96% - 99%. The fact that our air filters at times reach overall filtration efficiencies as high as 99% while maintaining high airflow is a testament to the quality and capabilities of our oil impregnated cotton air filter medium."
BUT they never claim that the other filters fail to meet the SAME standard.

K & N's second "daring" claim is: "We design our air filters to provide superior filtration of the contaminants that can harm your engine while maximizing the airflow characteristics of the filter in question. "

Here their key words are "design" and "superior". Nowhere do they provide a side-be-side comparison of their filter with the cheaper, paper filter. Also, they do not have claims or test results of: 1) how "washing" the K & N filter changes its characteristics or not, or 2) even how exactly to "wash" the filter.

So in the end, without clear evidence one way or the other, K & N leaves it up to our good sense :d to figure out what's true.

One final point. Trying to associate their filter with the loftier standards of competition race car teams, K & N writes:
" ... a road racer may elect to forgo an air filter in favor of large volumes of unrestricted air. However, testing the theory using an air filter enclosed in a vented housing should dispel the myth. The filter and housing will trap particles of loose trash kicked up by other race cars during the heat of battle. Dirt, small stones and pieces of shredded rubber expelled from soft compound racing tires can be found inside the housing after even a short race. Once a driver, car owner or engine builder realizes just how much trash is thrown around during a normal race, few would expose their expensive engines to unfiltered air in future events.

Whenever possible, performance enthusiasts should install a K&N 360 degree open-element filter. A correctly sized conical or round filter will deliver virtually unrestricted air flow. And, as we have learned, providing the engine with all of the air it needs promotes optimum performance. In a high speed application, a K&N filter will straighten the air which counteracts turbulence."

This would have been a good place for K & N to add an endorsement by: Andy Granatelli and Al Unser insisting that ONLY K & N filters be installed in their competition cars. But no. ALL of K & N's claims are hypothetical.

Based on the comments of our own K & N users (above) and the company's unqualified and unsubstantiated claims, I'd hang a rabbits foot next to the air box containing a K & N filter ... and hope for the best!

[ghostrider52005]

I run K &N pods on the wifes 700 intruder and still on the same set of filters after five years. The Intruder was "uncorked" so to speak back then by going to larger main jets and straight thru exhaust so open flow filters were a necessity.
I cant tell you how much of a performance increase if any the filters provided on their own since the large jets, exhaust mod and filters were all changed at the same time. There was a marked increase in performance of the bike but that was due to the larger jets and exhaust. The high flow k&n pods were put on simply to get enough air into the mix. I doubt on their own with no other modifications they would have done anything except perhaps lean the bike out a bit.
Yes in those days the wife was a hot rod and enjoyed blowing my Harley away with the 700 while signaling to me I was no 1 as she passed. :roll: :lol:
And yep there was no end of rejetting, racing clutch, exhaust mods being done to my Harley to try to prevent those little episodes from happening but to no avail. :cry:
Of course her 125 lbs vs my then 275 lbs may have a had a little to do with it. :-J :ymblushing:

[Ranch55]

I'm not going to try to sell anything.
Now then, how long will you have the motorcycle?
My 1984 Aspencade, of which I am the original owner, has had a K&N for the last 20 plus years. I have a spare K&N on the shelf, but have never had to use it. I am still running the original K&N air filter.
I do inspect it as required, and clean / re-oil as necessary. I won't make any claims about improved motorcycle performance, But, I have saved a bunch of money over the years from not having to purchase new OEM air cleaners.
Back to the top.
How long or how many miles do you plan on having the motorcycle?
I think that question needs to be answered before you can make your decision whether to go K&N or not.

[Granpah]

Thinking about picking up a K&N air filter for my Aspencade--is their a increase in performance?--are they worth the extra money? **==

AMSOIL came out with the first nano fiber filter containing a "secret" coating on it that they claim removes 15 to 50-times as much dust as conventional filters while allowing maximum air to pass through. BUT now the GL1200 version is no longer available, and only the GL1500 filter can be bought from them. A bigger BUT is that it costs $84!

The simple HIFLO AIR pleated paper filter mentioned above can nowadays be had for $10.51 + $7 shipping.That's what I've been using. So far, so good.


Finally, there's the so-called UNI foam-based filter out there costing $25 + $7 shipping discussed above by Vic and others, that has to be coated with oil (supplied free with the filter). That doesn't at all appeal to me. The AMSOIL nano fiber filter with the "magic" coating seemed more sensible but it's VERY expensive and no longer available for GL1200s.

[Gone14S]

I have a K/N.
Most of you are right. It is noisey. Does not make the bike run any better.
But in the long run it does save me money on air filters.

Kurt